Electrical connector for fluid cooled transformer windings



June 1951 H. A. STRICKLAND, JR 2,556,235

ELECTRICAL CONNECTOR FOR FLUID COOL-ED TRANSFORMER wmnmes Original Filed July 30, 1943 3 Sheets-Sheet 2 @ICrZ INVENTOR ir rcuold 9. S ricklcmd,

A TTORNE Y June 12, 1951 H. A. STRICKLAND, JR 2,556,23

ELECTRICAL CONNECTOR FOR FLUID coouzn TRANSFORMER WINDINGS 3 Sheets-Sheet 3 Original Filed July 50, 1943 INVENTOR Harold R. SI rLcQlandJr.

ATTORNEY Patented June 12, 1951 ELECTRICAL CONNECTOR FOR FLUID COQLED TRANSFORMER VVINDINGS Harold A. Strickland, Jr., Detroit, Mich., assignor,

by mesne assignments, to The Ohio Crankshaft Company, Cleveland, Ohio, a corporation of Ohio Original application July 30, 1943, Serial No.

496,719. Divided and this application July 16, 1946, Serial No. 684,052

This invention relates to electrical connectors usable in connection with transformer coils and similar electrical equipment.

In many electrical conductors, especially those intended for carrying heavy currents, it is desirable that the conductor be cooled, and a common method of cooling is to make the conductor tubular and force a, coolant through the conductor when carrying current so as to maintain the conductor temperature within the range of efiicient operation. Where the conductor is applied to an electrical unit, such as a transformer coil as disclosed in my .copending application Serial No. 496,719, filed July 30, 1943, now abandoned, of which this application is a division, there is usually a point of connection between the terminal of the unit and the external conductor which must take care not only of the break in the electrical circuit at this point, but also the break in the circuit of the coolant. Consequently, a connector must be provided which will insure a satisfactory electrical connection as well as a liquidproof joint.

An object of the invention is to provide a connector which will insure a leak-proof connection between two hollow conductors as well as a lowresistance electrical junction. 4

Another object of the invention is to provide a connector which permits connection at right angles to the terminal of the apparatus conductor terminal.

Another object of the invention is to provide a type of connector which may be applied easily to a plurality of tubular conductor terminals so as to facilitate parallel junction in an electrical circuit.

An additional object is to provide a connector which has particular applicabilit to the termnals of transformer coils.

Referring to the drawings:

Figure 1 shows an elevation of a transformer to which my invention is applied;

Figure 2 is a section of the transformer taken along the lines 22 of Figure 1;

Figure 3 is a plan View in section of the transformer along lines 33 of Figure 2;

Figure 4 is a sectional detail of the junction with a connector as applied to the secondary coil of the transformer; and

Figure 5 is a perspective view of the connector as applied to a plurality of conductor terminals.

The transformer of the present invention is illustrated as of a stationary type and including a primary coil 1 0 enclosed by a secondary coil I, as shown clearly in Figure 3 of the drawing.

As will appear from this figure and Figure 2, the primary coil is formed of two sections I2 and 1Claim. (Cl. I'M-15) 13, each section consisting of a number of square turns of hollow conducting material, as copper, placed side by side to form a hollow enclosure of rectangular formation. The ends of the primary sections l2 and i3 adjacent each other are radially out-turned, forming terminals l5 and [B which are side by side, as shown, to form a substantially unitary tap connection. The other ends of the sections, indicated by numerals I l and 18, are outwardly turned fromthe end coil turns in parallel relation to the coil axis to form points of connection to the coolant and bus bars. For this purpose the terminal end sections l1 and l8v are formed with the ends cut at an incline lflthrough' the tubular section, the incline terminating in an outer flattened extension 20.

Surrounding the primary unit it], the secondary II is formed also of two sections 2| and 22, section 2| overlying the primary coil section I2 intermediate the tap unit l5l6 and a point outwardly displaced from the edge of the primary coil; and the lower section similarly extending from the tap unit l5-l6 below the lower end primary 001. Each section of the secondary is formed of rectangular turns of tubular conducting material, all of the turns enclosing practically the whole peripheral area of the enclosed primary coil turn. These turns, however, are not con'-; tinuous, but broken, the ends having fixed and fluid-proof connection with two manifolds 24 and 25, the manifold 24 forming the closure for one, set of overlying secondary terminals and the. manifold 25 forming the closure for the adjacent overlying ends of the secondary. The mode of connection of these secondaries to the manifold is shown more particularly in Figures 3 to 6 of the drawing. From inspection of these figures it will appear that the manifold 24 consists of a block of material which should be electrically conducting, as metal, axially channeled on one edge to form the block faces 2'! and 28. Each secondary terminal is diagonally formed at its end with a flattened end piece 29, at the extreme end of which the edge of the clock face 28 is brazed or otherwise attached. The edge of the block face 21 is similarly attached to the outer surface of the secondary and the terminal sides are likewise sealed so that the fluid channel 26 has direct communication with the interior of the tubular secondaries. Since each secondary terminal is similarly attached to the manifold 24 and since. moreover, the same construction is followed in the formation of the junction between the manifold 25 and-the adjacent secondary terminals. it appears that by this construction there not only is secured an effective parallel electrical connection to the secondary turns of both sections of the 3 secondary to the manifolds 24 and 25, but also a complete and satisfactory means of liquid communication is obtained, which is effective for all of the turns of the secondary coil.

Provision for inflow and outflow of liquid into the manifold is made by insertion of ducts 30 and 3| in the manifolds 24 and 25, respectively, which ducts are screw-threaded to receive connecting nipples for transmission of an appropriate cooling liquid. Two of these ducts are formed in the manifold, either one of which may serve as the inlet or the outlet opening.

Inasmuch as these are two separate secondary coil assemblies, they must be electrically connected in parallel. To do this and support the manifolds 24 and 25 in relation to the transformer as a whole, use is made of the supporting and electrically conducting attaching bars 32 and 33, the bar 32 being fixed against the manifold 24 and the bar 33 against the manifold 25 and bolted thereto by means of bolts 34, as indicated in dotted outline in Figure 4 and shown in Figure 1. Additional rigidity is given to this manifold structure by use of a transverse bolt 35, as shown in Figure 4, the bolted structure including the screw-threaded plate 36, insulation strip 31, manifold 24, intermanifold strip insulation 38, manifold 25, insulation strip 39, metal plate 49, bolt enclosing insulation strip 80, and bolt head 4|. Reference is made to Figure 5 as clarifying the mode of connection of the secondary terminals (indicated in dotted outline) to the manifold 24 or 25, this view bringing out the lesser depth of the face 21 which overlies the tubing,

as contrasted to the face 28 of the manifold which overlies the flattened end piece 29 of the tubing.

Insulation between the various turns of the coils of the primary is indicated by the numeral 42 in Figure 2. Also, insulation is provided between the metal of the transformer structure and the primary coil by the insulation strip 44 and between the primary and secondary coil by the insulation strips 45. It is pointed out that the turns of both primary and secondary are substantially rectangular in section so as to facilitate assembly.

The coils of the transformer are placed in proper magnetic relationship to the core 41, which in the present showing is of the shell type having a central branch 48 enclosed by the coils and connected external branches 49 forming a closed magnetic path from end to end of the coils.

'To provide an adjustable support for the transformer as a whole, use is made of angle plates 56 having a vertical section secured by bolts 51 to the vertical angle plates 54, as shown in Figure 2, and a horizontal section receiving the bolt 58 screw-threaded therein, the bolt being adjustable vertically by threads in angle plate 56 and locked by means of the nut 52. Since there are four of these supporting bolts 58, it is apparent that any desired adjustment of the transformer relative to the vertical may be made.

The inner core section 48 supports the coil units of the transformer, the core lying within the coil assembly and the whole unit positioned as shown in Figure 1 and Figure 3. The secondary outlet connections including the manifolds 24 and 25 are on one side of the transformer and the primary connections on the other side. The secondary connections are supported on the frame of the transformer enclosure by attaching means including the screw-threaded wing plates 60 on either side of the supporting blocks for the manifold elements.

The adjacent middle terminals l5l6 of the primary coils are enclosed in an electrically con ductin conduit 69 leading to a pipe filter T 10 to which, by means of the pipe connection ll, cooling fluid is supplied the primary circuit through a rubber hose. Thi fluid flows through the primary sections from the central inlet point 69 and is removed through the tubular connectors GI and 8|.

It is worthy of note that the arrangement of manifold connection to the secondary turns is such as not to increase appreciably the resistance or reactance of the secondary circuit and that this arrangement also facilitates cooling as desired and permits easy adjustment of the load circuit connections. In general, the efficient cooling means in the construction as described makes possible an increased output by reducing the average temperature of the windings without reducing the effective area of coil turns. By reducing the average temperature of coils, the rate of ageing of the insulation of the winding is also reduced so that the life of the transformer is proportionally increased. In addition, the construction facilitates modification of output since, for example, only one section of the primary may be used.

Modifications oi the construction to meet minor requirements of installation and equipment may, of course, be made, the invention beingcompre hended within the claim hereunto appended.

What is claimed is:

Apparatus of the type described comprising in combination a terminal block generally U-shaped in cross section, the legs of the U defining a channel extending generally the entire length of the terminal block, one of said legs being shorter than the other by a predetermined amount; and a plurality of hollow conductors generally rectangular in cross section each having a pair of opposed first side walls and a pair of opposed second side walls, one of said second side walls and said pair of first side walls terminating short of the end of the other of said second side walls, said conductors being arranged with their first side walls in side-by-side relationship with the ends of each extending across the openin of said terminal block, said shortened second side wall engaging and terminating adjacent said shorter leg, said other second side wall engaging and terminating adjacent the longer of said legs whereby said conductors may close the opening of the channel of said terminal block with the hollow of the conductorsin communication with the channel.

HAROLD A. STRICKLAND, J a.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,128,086 Gakle Aug. 23, 1938 2,181,644 Seifert Nov. 28, 1939 2,193,977 Martin Mar. 19, 1940 2,308,673 Burgett Jan, 19, 1943 2,318,024 Strickland, Jr. May 4, 943

FOREIGN PATENTS Number Country Date 171,836 Great Britain Dec. 1, 1921 

